Reaction from surgery?

I had spinal fusion last Thursday and now have bumps showing up all around my neck area. They go from ear to ear and down to about where neck joins shoulders and it itches like crazy. Talked to doctor this morning about blister like bumps showing up around stapled area and he told me to stop the neosporin. Now i have bumps like you get from heat showing up and i'm getting worried. Could this just be a reaction to surgery or something that i need to be worried about?